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Date: Fri, 25 Oct 2024 12:30:32 -0700 (PDT)
From: "Christoph Lameter (Ampere)" <cl@gentwo.org>
To: Peter Zijlstra <peterz@infradead.org>
cc: Linus Torvalds <torvalds@linux-foundation.org>, 
    Will Deacon <will@kernel.org>, Thomas Gleixner <tglx@linutronix.de>, 
    Catalin Marinas <catalin.marinas@arm.com>, Ingo Molnar <mingo@redhat.com>, 
    Waiman Long <longman@redhat.com>, Boqun Feng <boqun.feng@gmail.com>, 
    linux-mm@kvack.org, linux-kernel@vger.kernel.org, 
    linux-arm-kernel@lists.infradead.org, linux-arch@vger.kernel.org
Subject: Re: [PATCH v3] Avoid memory barrier in read_seqcount() through load
 acquire
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On Fri, 25 Oct 2024, Peter Zijlstra wrote:

> > atomic_inc_release(&seqcount)
>
> It would not be, making the increment itself atomic would make the whole
> thing far more expensive.

True. I was too much taken by a cool hw feature on ARM.